2000 Vol. 13, No. 4
The present study was initiated to make an urban-rural comparison of the prevalence of cases positive to hepatitis B and C virus (HBV and HCV, respectively) infection markers in densely populated eastern half of China. For this purpose, 10 survey sites were selected, i.e., six sites in urban areas (the city group; Beijing, Shanghai and four provincial capitals) and four sites in rural areas (the village group ; one village each in Jilin and Shandong Provinces, and two villages in Shaanxi Province). About 50 adult women per site volunteered to participate, from whom 494 valid blood samples were collected. Positivities to HBsAg (HBsAg+), anti-HBs (anti-HBs+) and anti-HBc (anti-HBc+) were examined by RIA methods, and that to anti-HCV (anti-HCV+) by either EIA or RIA. Those positive to any one of the three HBV infection markers were taken as HBV infection-positive (HBV+). The prevalence of HBsAg+, HBV+ and anti-HBc+ was 8%, 70% and 2.7% in the city group, and 8%, 65% and 2.0% in the village group, and no significant difference was found between the two groups. The overall prevalence was 8% for HBsAg+, 68% for HBV+, and 2.4% for anti-HCV+. The results were discussed in reference to some 20 papers each on HBV+ and anti-HCV+ prevalence in China published since 1991. The reviewing of these papers confirmed that the prevalence of HBV was high (i.e., in excess of 50%), whereas the prevalence of anti-HCV was low (well below 5%), and that no substantial difference was found between the rural and urban populations.
To study the relationship of oxidative, antioxidative constituents and antioxidases in blood with chronic cholecystitis containing gallstone, levels of lipoperoxides (LPO), nitric oxide (NO), vitamin C(VC), vitamin E (VE) and β-carotene (β-CAR) in plasma as well as level of LPO, activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in erythrocytes were investigated by spectrophotometric assay in 107 patients with this condition (PCg) and 100 healthy volunteers (HVs). Compared with HVs group, the average value of LPO and NO in plasma and that of LPO in erythrocytes of PCg group were significantly increased (P<0.0001), while that of VC, VE and β-CAR in plasma and the average activities of SOD, CAT and GSH-Px in erythrocytes were significantly decreased (P<0.0001). Linear regression and correlation analysis for 107 preoperative PCg showed that the value of LPO and NO in plasma and that of LPO in erythrocytes of PCg gradually increased (P<0.0001), representing a significant linear positive correlation. The value of VC, VE and β-CAR in plasma and that of SOD, CAT and GSH-Px in erythrocytes of PCg gradually decreased (P<0.0001), representing a significant linear negative correlation. Stepwise regression and correlation analysis for 107 preoperative PCg suggested that the closest correlation was observed between the course of disease and the value of NO and VC in plasma and that of SOD, GSH-Px and LPO in erythrocytes, r=0.7306, F=32.1408, P<0.0001. Compared with the preoperative PCg group, the average value of LPO and NO in plasma and that of LPO in erythrocytes of the postoperative PCg group were significantly decreased (P<0.0001). Furthermore, the average value of VC in plasma and that of SOD, CAT and GSH-Px in erythrocytes of the postoperative PCg group were significantly increased (P<0.0001), whereas no significant difference was found between their average value of VE and β-CAR in plasma. These findings suggested that oxidative stress was an aggravating pathological condition in PCg group. Therefore, we recommend that in treating PCg, antioxidants such as VC, VE, β-CAR should be given in order to alleviate their potential oxidative damages.
To investigate the epidemiological characteristics of childhood type 1 diabetes mellitus in China, newly diagnosed cases of type 1 diabetes with an onset age under 15 years were retrospectively registered by 23 local centers in China following a standardized protocal on the basis of the nationwide registry established by the WHO DiaMond Project China Participating Center, Chinese Academy of Preventive Medicine (CAPM). A population of about 24 million children were covered in the defined areas . A two-sample capture-recapture method was used to estimate case ascertainment. Between 1988 and 1996, 903 diabetic cases were registered in 9 ethnic groups. The overall ascertainment corrected incidence rate (IR) was 0.59 per 100 000 person-year. The IR was 0.52/100,000（95%CI：0.50～0.54）for males and 0.66/100,000（95%CI：0.64～0.68）for females. The standardized ascertainment corrected IR by the national age-specific population in 1990 was 0.57 per 100,000 person-year. The incidence among various ethnic groups ranged from 0.25/100,000 to 3.06/100,000. The IRs increased with northern latitude, and the IR of Han population was significantly higher in North China compared with South China (0.67 versus 0.53 per 100,000 respectively, P<0.01). A correlation model of incidence and calendar time showed that the IR increased significantly between 1988 and 1996 (r=0.86, P=0.0027). The relative risk (RR) of type 1 diabetes mellitus for different age-groups estimated by a Poisson regression model showed that taking RR as 1.00 for age-group from 0 to 4 years, the RR for age-group from 5 to 9 year and from 10 to 14 year was 2.30 and 3.60 respectively. The standardized ascertainment corrected IR of childhood type 1 diabetes mellitus in China is much lower than in other countries. The geographic and ethnic variability of the incidence suggests that both genetic and environmental factors play a role in the development of childhood diabetes in China.
Toxicology is a science that studies the deleterious interactions between chemicals and living organisms. This definition covers living organisms related to the problem to be analyzed: man, insects and trypanosomes.
Chagas' disease, also known as American trypanosomiasis, is an endemic parasitic disease limited to the tropical and subtropical countries of Latin America (Pinto Díaz, 1984; WHO, 1981, 1985; Schirmer, Muller, and Krauthsiegel, 1995; Castro and Toranzo, 1988; Docampo and Moreno, 1985; Fairlamb, 1982). It is estimated that at least 20 million persons are infected with the etiologic agent of the disease, Trypanosoma cruzi (Pinto Díaz, 1984; WHO, 1981, 1985; Schirmer, Muller, and Krauthsiegel, 1995; Castro and Toranzo, 1988; Docampo and Moreno, 1985; Fairlamb, 1982). Further, more than 40 million are living under conditions where they may be bitten by the vector insect infected with the parasite (Pinto Díaz, 1984; WHO, 1981, 1985; Schirmer, Muller, and Krauthsiegel, 1995; Castro and Toranzo, 1988; Docampo and Moreno, 1985; Fairlamb, 1982). About 120 000 new cases per year were reported (Pinto Díaz, 1984; WHO, 1981, 1985; Schirmer, Muller, and Krauthsiegel, 1995; Castro and Toranzo, 1988; Docampo and Moreno, 1985; Fairlamb, 1982). The infection results because the vector insects (a Reduvii bug) have hematophagous habits, and because these blood sucking organisms, usually defecate immediately after having their meal. As a result, the infected feces find their way into the host bloodstream through a bite wound in the skin or via intact mucous membrane or the conjunctiva (Pinto Díaz, 1984; WHO, 1981, 1985; Schirmer, Muller, and Krauthsiegel, 1995; Castro and Toranzo, 1988; Docampo and Moreno, 1985; Fairlamb, 1982).
The relationship between maternal nutrient intake and fetal size or infant growth was studied in 1956 pregnant women, 599 parturients and 1043 lactating women, 318 non-pregnant women included as controls. The study was conducted in eight regions that were representative of all geographical areas of China. The diet was comprised primarily of cereal products with 70% to 85% of the zinc intake derived from plant sources. Women in the third trimester of pregnancy, parturients and lactating women consumed more food than non-pregnant women or women in the first two trimesters of pregnancy. Total energy, protein and iron intakes met the recommended allowances for each stage of reproduction. Calcium and zinc intakes, however, were 50% and 47% of the amount recommended, respectively. Only 7.2% of the women exceeded two-thirds of the recommended zinc intake. The mean intake of zinc was 6.5mg to 9.0 mg each day among all the subjects. Correlation and stepwise regression analysis showed that maternal zinc intake was a predictor factor for fetal dimensions and birthweight. The results of this study show that fetal growth and birthweight are directly related to maternal zinc intake among Chinese women, and that there is no relationship between maternal zinc intake during lactation and infant height, weight, or weight gain from birth.
To study the suppression effect of light rare earth elements (RE) on proliferation of two cancer cell lines. Two cancer cell lines PAMC82 and K562 were used to examine their colony-forming ability in soft agar, microtubule structure, calmodulin levels and regulation of some gene expressions by Northern blot analysis with and without treatment by RE. The results showed that on soft agar culture the colony-forming ability of human gastric cancer cell line PAMC82 treated by RE chloride decreased and the PAMC82 cell microtubule abnormal structure became normal. The calmodulin (CaM) levels decreased in human leukemia cells (K562) treated with cerium chloride and neodymium chloride. The Northern blot analysis revealed marked up-regulation of p53, p16(MTS1), p21(WAF1) gene expressions in PAMC82 cells treated with lanthanum chloride and cerium chloride, as compared to control PAMC82 cells. The light rare earth elements studied have certain suppression effects on proliferation of cancer cells. This effect might be related to the decrease of calmodulin and up-regulation of some gene expressions in cancer cells.
Kombucha tea (KT) is a popular health beverage and is used as an alternative therapy. KT is prepared by placing the kombucha culture in solution of tea and sugar and allowing to ferment. The inoculum is a fungus consisting of symbiotic colony of yeast and bacteria. KT is consumed in several countries and is believed to have prophylactic and therapeutic benefits in a wide variety of ailments, viz., intestinal disorders, arthritis, ageing and stimulation of immunological system. Though KT is used in several parts of the world its beneficial effects and adverse effects have not been scientifically evaluated. Since there are no animal toxicological data on KT, subacute oral toxicity study was carried out. Five groups of rats were maintained: (a) control group given tap water orally, (b) KT given 2 ml/kg orally, (c) plain tea (PT) given 2 ml/kg orally, (d) KT given in drinking water, 1% (v/v) and (e) PT given in drinking water, 1% (v/v). The rats were given this treatment daily for a period of 90 days. Weekly records of weight, feed intake, water intake and general behaviour were monitored. There was no significant difference in the growth of the animals as evidenced by the progressive body weight change. The organ to body weight ratio and histological evaluation did not show any toxic signs. The haematological and biochemical variables were within the clinical limits. The study indicates that rats fed KT for 90 days showed no toxic effects.
2000, 13(4): 300-306.
The total quantity control of pollutant emissions for an industrial district is determined by coefficient (A) method (Qian, 1990). It is suggested that average daily concentrations of air pollutants should be estimated in relation with metrological parameters, such as wind directions, wind speed and atmospheric stability in the period of monitoring by Gaussian model (SEPB, 1991), and that the sources of pollution should be redistributed on the basis of the result of monitoring with a view improving local atmosphere environment.
The cost-effectiveness of DOTS (Directly Observed Treatment, short course) and non-DOTS strategies for smear-positive pulmonary tuberculosis in Beijing was evaluated. Cost calculation was based on the expenses of drugs, chest X-ray films, sputum smears and cultures for the patients. Effectiveness of the intervention was assessed in two aspects: direct benefits to the patients treated and indirect benefits to the others through reduced transmission of tuberculosis; disability adjusted life of year (DALY) was used as an index. The results showed that one DALY could be saved with 45.7 Yuan by DOTS and 471.4 Yuan by non-DOTS. DOTS is a good control strategy for smear-positive tuberculosis.
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